The application relates to a penetration-resistant article having a woven fabric structure, said fabric structure having high-strength fibres with a strength of at least 1100 MPa in accordance with ASTM D-885 and thermoplastic fibres.
Until now a pre-impregnation process (prepreg) has been used for the production of penetration-resistant articles made from woven layers of high-strength fibres during which a film or resin was applied to a woven layer. After the calendering step, several pre-impregnated woven layers were stacked and compacted under high temperature and pressure to create the desired material, e.g., reinforcing plates. This method caused several problems. The material calendered onto the fabric of high-strength fibres contains solvents. Under normal atmospheric conditions, the solvent diffuses rapidly so that the resin film also ages. In order to avoid this, cooled transport and cooled storage of the pre-impregnated fabrics are necessary. Furthermore, the drapability of the woven layers in small radii is low. The calendering of the woven layers is also very cost-intensive. The additional product step costs time and energy and a release film is required between machine and resin film in order to prevent sticking of the coated material to parts of the production machines, but also to the next roll layer (when producing roll stock). The pre-impregnation process can be avoided by a textile engineering solution in which a thermoplastic yarn is woven together with the high-strength yarns so that during compaction and forming of the article made from several fabric layers under increased temperature and pressure, the thermoplastic becomes fluid and joins the woven layers together like an adhesive.
Articles made from several woven layers, also for ballistic protection, are known. The use of hybrid fabrics of thermoplastic and high-strength fibres in one of these woven layers is also known.
U.S. Pat. No. 5,168,006 describes a woven fabric in which thermoplastic and high-strength fibres are woven together before being compacted to create mouldable materials. Here the two fibres are woven in parallel as warp and weft threads, respectively, in a warp beam system. The fabric is characterized by a high thermoplastics content.
The avoidance of the pre-impregnation process by textile engineering measures is also known.
EP0417827 describes a woven fabric of thermoplastic fibres and high-strength fibres that can be used as a pre-impregnated material for the production of, for example, protective clothing (helmets). Pretreated thermoplastic fibres are joined with the high-strength fibres to form fibre bundles that are subsequently woven, with the high-strength fibres accounting for preferably 40-60% of the fabric.
The articles described in the published literature all have the disadvantage, however, of only a low penetration-resistant effect and the drapability of the articles is also low. The latter effect is predominantly attributable to the high thermoplastic content of the woven fabric.
Document DE 10 2011 102 342 describes a multi-layer textile with at least one double layer. A first ply of this multi-layer textile contains reinforcing threads while a second ply of the multi-layer textile contains matrix threads. The reinforcing threads should have a structured arrangement in the multi-layer textile [0009] so that they form, for example, a non-crimp fabric. The two plies are joined together using binder yarns. The document does not describe that the reinforcing threads arranged in the structure form a woven fabric of reinforcing threads. The advanced synchron weave structure (described in EP 0408830) is mentioned in paragraph [0016] as a preferred embodiment of the multi-layer textile. In this structure, the reinforcing threads form two non-crimp fabric layers that cross one another and the matrix threads hold the reinforcing threads together by interlaced upper weft threads or lower weft threads. The matrix material is consequently located between the reinforcing threads. The objective of the invention according to DE 10 2011 102 432 is the ideal uniform distribution of the matrix threads so that when the matrix material melts, each filament of the reinforcing fibres is wetted with the matrix material. In order to achieve this, the reinforcing threads must not have the form of a woven fabric, as otherwise a uniform distribution of the matrix material at the crossing points of the fabric would not be possible. Furthermore, the infiltration of the matrix material into such a fabric of reinforcing fibres is more difficult. The flat textile described in this document can be used as an outer skin for aircraft, motor vehicles or other vehicles (paragraph [0022]). Due to the fact that the filaments of the reinforcing fibres are uniformly wetted by the matrix material, the ballistic retention capacity would be significantly reduced so that the material of DE 10 2011 102 432 cannot be used for antiballistic purposes.